An existing problem being faced in the development of new vaccines is the need for targeting bacterial infections that occur at mucosal sites such as the upper airway and the gastrointestinal tract. Overcoming this problem will require the use of novel vaccine formulations and the use of novel immune enhancing agents (adjuvants) that promote immune responses that are effective at mucosal sites. This study will explore the additive and potentially synergistic activities of a combination adjuvant for their ability to specifically induce a balanced immune response to a novel subunit vaccine designed to prevent infection by an enteric pathogen. This project will support formulation activities and the evaluation of protective efficacy in an animal model.